W ‘ J W 1W £3.23 WWI THE fiFFlECT 0F FORAGE fiiAflAGEhfiENT UPCN SUt3SEQUEN? WELDS Q? CGRN AND OATS Thesis for fhe Degree of M. S. M1CHEGAN STATE COLLEGE Mark Richard Earmfi' 1955 g . This is to certify that the thesis entitled THE EFFECT OF FORAGE MANAGEMENT UPON SUBSEQUENT YIELD OF (DRN AND OATS presented by Mark Richard Bermtt has been accepted towards fulfillment of the requirements for MS Farm Crops degree in Major professor Datemmrmssé 0-169 —..——7._r ____.______ __ f, , W PLACE ll RETURN BOXto remove“- chockout from your record. TO AVOID FINES return on or before date duo. DATE DUE DATE DUE DATE DUE 1fhi‘lrs .u I 1.71vafl ; K THE EFFECT OF FORAGE MANAGEMENT UPON SUBSEQHENT YIELDS OF CORN AND OATS By Mark Richard Berrett w A THESIS Submitted to the School of Graduate Studies of Michigan State College of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Farm Crops 1955 ACKNOWLEDGMENT The author wishes to express his sincere appreciation to Dr. C. M. Harrison for his guidance throughout this study and for his helpful suggestions in the preparation of the manuscript. Acknowledgment is also made to Professor H. M. Brown for his assistance with the statistical analysis and to Mr. Grant Nichol of the Monitor Sugar Division for his assistance with the field work. The author is grateful to the Farmers & Manufacturers Beet Sugar Association for the funds which made this study possible. n MARK RICHARD BERRETT ABSTRACT A previous experiment was conducted in 1950-52 (1) on several forage species fertilized at various rates and managed in different ‘ways to test the effects of such practices on sugar beet production the year following. The present experiment is a study of the possi- ble carrybover effect of these forages and practices on corn and oats following the beets in the rotation. Under the conditions of this experiment, there was a marked dif- ference in the way forages affected subsequent corn yields. The re- sponse of corn to the original fertilizer application on the forages was not significant. The corn yields, from.plots where the forage had been previously left on, were higher for every forage species and mix- ture than corn yields where the hay was removed. The increase in corn yields resulting from the application of 800 pounds of 3-9-18 on the beets preceding corn was highly significant over yields where no fer- tilizer was previously applied on the beets. The fertilizer applied in 1950, while beneficial to yields of forage in 1951 and beets in 1952, did not benefit corn in 1953 and oats in 19Sh. Oat yields in 1951; were generally higher on plots where the hay had been previously left on in 1951. The results of this experiment indicate that even though forages are beneficial in a rotation, they are not a substitute for periodic, liberal applications of commercial fertilizer. (1) Erdmann, M. H., The effect of forage management on a subsequent sugar beet crop, Ph.D. Thesis, 1953, Mich. State College. TABLE OF CONTENTS Page INTRODUCTION ------------------------ 1 REVIEW OF LITERATURE -------------------- 3 EXPERIMENTAL PROCEDURE ------------------- 6 EXPERIMENTAL RESULTS - ------------------- 8 DISCUSSION ------------------------- 18 SUMMARY -------------------------- 23 LITERATURE CITED ...................... 25 at. NEEfiMVMLI‘A Vanna“ .1 . THE EFFECT OF FORAGE MANAGEMENT UPON SUBSEQUENT YIELDS OF CORN AND OATS INTRODUCTION The value of forages in maintaining or increasing soil fertility has long been established. History reveals that the Greeks turned un- der broadbeans 300 years before the time of Christ, and the planting of lupines and beans for soil-improvement was a common practice in the early years of the Roman empire. (1) Forage crops, as a group, are included in.many rotations not only as a source of roughage for livestock but also because of their bene- ficial effect on soil structure and fertility. The organic material which is contributed to the soil frequently shows an effect in terms of added crop yields for those crOps which follow the plowing down of a forage crop. Among the benefits which accrue from the addition of or- ganic material to the soil are: (1) improved aeration, (2) retarded puddling when soil is worked too wet, (3) easier water penetration, thereby reducing surface runoff and consequent erosion, (h) increased availability of some nutrients. Forages vary in their ability to produce under given soil and cli- matic conditions such as temperature, rainfall, and soil drainage. Management of the forage crops likewise may'affect the degree to which they benefit subsequent crops in a rotation. Mixtures used, fertilizer rates, plowing down or removal of forage, severeness of cutting or graz- ing, and time of cutting or grazing are all management problems which.may affect the value of forages in a crop rotation. 1 An experiment was conducted in 1950-52 (2) on several forage species fertilized at various rates and managed in different ways to test the effects of such practices on sugar beet production the year following. The present experiment was set up to study the pos- sible carry-over effect of these forages and practices through the beet crop to corn and oats following in the rotation. REVIEW OF LITERATURE The literature which emphasizes the influence forages have upon subsequent crop yields is fairly voluminous. This influence has been evaluated in terms of effect upon soil structure and nutrient avail- ability as well as in its' effect upon yields of various crops. Pieters (9) stated in 1927 that green manuring practices had shown an increase in yield of corn, small grains, cotton, beets, potatoes, sugar cane, and tobacco. He noted that it was not uncommon to find cases where green manure failed to increase yields. Purvis and Blume (3) in their work in Virginia found that plowing down sorghum and soybeans alone or a.mixture of the two induced a.marked increase in potato yields. Fresh organic matter was about three times as effective as residual organic matter in producing increased yields due to the release of plant nutrients through decomposition. Hester (h) noted that potato yields in a rotation which included either legumes or non-legumes as a cover cr0p were 11-18% higher than those in a cash crop rotation. Bushnell (16) reported that corn used as green.manure gave larger amounts of organic matter and resulted in higher potato yields than did soybeans or sweet clover. The nitrogen requirements for potatoes were met by including h0-80 pounds of nitrogen.per acre in the regular fertilizer. The work of Gardner and Robertson (8) in Colorado showed that al- falfa in a rotation contributed materially to yields of corn, wheat, barley and sugar beets on soils which were not well supplied with nitro- gen-carrying materials, but the benefits of alfalfa did not minimize the necessity for mineral fertilizers. Harrison gt El. (6) found that corn 3 yields from plots which had been previously pastured continuously were significantly higher than.yields from plots which had been both pas- tured and out for hay or cut for hay alone. These workers also noted a significant increase in subsequent corn yields from mixtures con- taining alfalfa over those which did not contain alfalfa. Nielsen .22.§l' (5) in their work with corn in Ohio observed that the decompo- sition of alfalfa in the soil increased the availability of residual phosphorous. MdKraig 32 El. (7) reported from South Carolina that leguminous green.manure in summer, followed by'a winter cover crop of rye, main- tained the soil carbon and nitrogen at a higher level and resulted in higher yields of cotton and corn than a summer cover crop with winter fallow. Over a nine year period in Arkansas, Martin (10) found that adapted legumes, such as hairy vetch, crimson clover and Austrian‘winter peas planted in the fall and turned under in the spring, produced marked yield increases of cotton, corn and rice. Moser (12) noted significant differences in yields of sorghum and rye on soils containing leguminous residues over soils which had received commercial fertilizer alone. He observed also that legumes rendered phosphorous and potassium more available. Andharia gt 21. (1h) reported that corn plots in rotations, which included one or more years of a mixture of alfalfa, red clover and brome grass, contained signi- ficantly higher amounts of organic matter and nitrogen than did plots in a corn-oats rotation. Growther and Mirchandani (15) found in England that there was no benefit to yields of winter wheat resulting from plowing down vetch and summer mustard. Their suggested reason was that the production of h ammonia and nitrates came at a time when the wheat was unable to use them efficiently and consequently they were lost in drainage water. Tidmore and Volk (11) noted that for the purpose of conserving nitro- gen in the soil it was better to plow soybeans under in the spring rather than fall. This was due to the nitrification and subsequent leaching of nitrates during the fall. They further observed that over a nine year period the total organic matter content of the soil was in- creased 60% as a result of plowing down legumes every other year and that soils where legumes were plowed under were 30% higher in nitrogen when compared to similar soils where no legumes were plowed under. Robertson (13) reported that yields of corn and sugar beets were markedly increased.when forages were included in the rotation, and that one year of forage was as beneficial as two. The average results over a nine year period showed that beets following corn which had followed alfalfa produced yields equal to beets directly after alfalfa. Corn yields were lower when grown after beets following alfalfa-brome than when corn was grown directly after the forage. The forage crops de- finitely improved the soil structure. EXPERIMENTAL PROCEDURE A series of forage seedings were established in the spring of 1950 on Monitor Sugar Division.property in Bay City, Michigan. The soil is Kawkawlin loam and had not been planted to a sod crop for over 20 years. At the time of seeding, 2-lh-8 fertilizer was applied at three different rates, hOO lbs., 800 lbs., 1600 lbs. In addition check plots were left unfertilized. .Each treatment was replicated 3 times. Forages and mixtures used in the experiment were alfalfa, ladino clover, orchard grass, smooth brome grass, ladino-orchard grass, alfalfa- orchard grass, alfalfa-brome grass, and ladino-brome grass. Check plots were left on which no forage seeding was made. The forage plots were 792 ft. long and 28 ft. wide. The fertilizer plots and checks were laid out at right angles to the forages and were 252 ft. long and 66 ft. wide. The forages were out twice during the summer of 1951. All the forage from both cuttings was removed from half of each fertilizer plot and was left on the other half. Forage yields were taken for each cutting. The area was plowed in the fall of 1951 and planted to sugar beets the following spring. One half of each original forage plot was ferti- lized with 800 lbs. of 3-9-18 at the time the beets were planted. The results of the forage and sugar beet yields have previously been reported by Erdmann. (2) In the spring of 1953, the area was planted to corn, using Michigan hybrid 250. The corn was planted in hills with 36 inch spacing in the row and h2 inches between rows and thinned to three plants per hill. Those hills in which less than three plants emerged were replanted in an attempt to gain a perfect stand. The two center rows of corn in each plot were harvested. In the case of hills where there were less than three plants at harvest, ears were picked from an adjacent row in the same plot so theoretically, a perfect stand of three plants per hill was harvested. The ears in each plot were counted and weighed. Moisture samples were taken from 10 ears selected at random from each of 6 plots for each harvest day. The corn yields are reported on an oven dry basis. The area was plowed in the fall of 1953 and sown to oats with a seeding in the spring of 195h. The oats were not harvested separately from each individual plot. Using a self-propelled combine, two swaths, each 12 ft. wide, were harvested from each of the orginal fertilizer plots and checks, making a total of 2h swaths. One swath was cut in the area in which the forage had been left on and another where the forage was removed. Moisture samples were taken and yields reported on an oven dry basis. EXPERIMENTAL RESULTS The analysis of the corn yields shows a significant difference between plots following the previous forage seedings (Table l). The highest yield of 90.1 bushels per acreras obtained after ladino clover alone and the lowest yield of 79.9 bushels per acre came after brome grass alone (Table 2). The check plot, where no forage seeding ‘was made, produced 8h.5 bushels per acre. This yield was not signi- ficantly different from the average yield following the forages. The yield from the check plot was higher than those obtained following al- falfa, alfalfa-brome, brome and ladino-brome. Orchard grass alone pro- duced yields of about 2 bushels per acre more than alfalfa alone but a mixture of alfalfa-orchard gave yields of over A bushels per acre more than alfalfa alone. The yields following forage combinations were significantly higher than yields following single forage species (Table 3). Yields after legumes alone were significantly higher than those following grasses alone. Orchard grass alone was significantly better than brome in increasing corn yields. Likewise, mixtures containing orchard grass produced yields significantly higher than those containing brome grass. The difference in yields following ladino alone and those after alfalfa alone was significant in favor of ladino. Yields following combina- tions containing ladino were significantly better than those after mixtures containing alfalfa. The response of corn to the original fertilizer application was not significant (Table l). The average yield for the check plots was 8h bushels per acre while the average yield from.plots receiving 1600 pounds 2-1hr8 was 86.1 bushels per acre (Table 2). 8 Table 1 -- Analysis of variance of Corn Yields. Sourggof variation DF 33 MS F Main Plots R 2 18.13 7.06 .23 F 3 27h.80 91.60 3.0h Error 1 6 180.87 30.1h Sub Plots M 8 ut25.29 553.16 27.6h** f x m. 2h 230.h0 9.60 .h8 Error 2 6h 1280.33 20.01 Sub Sub Plots H 1 111.63 111.63 8.9h** f x h 3 55.39 18.h6 1.h8 m x h 8 31.22 3.90 .31 f x m.x h 2t 150.86 6.29 .50 Error 3 72 898.61 12.86 Sub Sub Sub Plots A 1 66.11 66.11 7.19** f x a 3 11.52 3.88 .t2 l.x a 8 586.83 73.35 7.98** h.x a 1 6.50 6.50 .Tl r x m.x a 2h 207.87 8.6u .9h f x h.x a 3 69.11 23.03 2.50 m.x h x a 8 h0.30 5.0h .55 r x m.x h.x a 2h 93.55 3.90 .t2 Error h 1th 1323.75 9.19 ** Significant at 1% level 89 Replications F- Original fertilizer M—Forage species and mixtures HFHay left on or taken off A-Fertilizer applied or left off beets Table 2 - Average Yield of Corn in Bushels per Acre Regardless of Whether or not the Forage was Removed from the Plot and Whether or not the Previously Planted Beets Re- ceived Fertilizer. Average Yield of Corn in Bushels per Acre Pounds of 2-IH48 Fertilizer Applied per Acre on Original Forage Seeding Forage Species and Mixtures 0 hOO 800 1600 Average Check 83.9 83.5 88.5 86.0 88.5 Single Grasses Orchard 83.9 83.6 86.1 85.9 8h.9 Brome 79.6 79.0 79.5 81.8 79.9 Single Legumes Ladino 89.8 89.7 89.9 90.9 90.1 Alfalfa 81.7 83.3 8h.h 81.9 82.8 Mixtures Ladino-orchard 87.3 89.2 89.8 91.8 89.h Ladino-brome 82.5 82.9 8h.5 86.3 8h.0 Alfalfa-orchard 87.1 85.6 87.3 87.6 87.0 Alfalfa-brome 80.5 82.1 81.7 82.7 81.8 Average 8h.0 8h.3 85.5 86.1 8h.9 10 Table 3 -- The Division of the Forage Species and Mixtures (M) into Single Degrees of Freedom. Source of variation DF SS MS F Check: Mixtures l 10.37 10.37 Singles: Combinations 1 121.16 121.16 6.05% Grasses: Legumes 1 797.08 797.08 39.85** Between Grasses 1 613.07 613.07 30.65** Between Legumes 1 1265.85 1265.85 63.29** Between Grass Combinations 1 1361.60 1361.60 68.08** Between Legume Combinations 1 256.00 256.00 12.80** Interaction l .16 .16 Error 2 from Table 1 6h 1280.33 20.01 * Significant at 5% Level ** Significant at 1% Level 1‘11 I A II . NEW” .1 IN , hl'fl sqil a. Table h -- Average Yield of Corn in Bushels per Acre Comparing Plots Where Hay was Left on and Where it was Removed Regardless of Whether or not Beets Were Fertilized. Average Yield of Corn in Bushels per Acre Forage Species Pounds of 2-1h-8 Fertilizer Applied Per Acre and Mixtures hOO 800 1600 Average Hay On Off On Off On Off On Off On Off Check 83.9 8h.0 85.7 81.3 85.2 8h.0 85.h 86.6 85.0 8h.0 Single Grasses Orchard 83.6 8h.3 83.9 83.6 86.7 85.6 87.2 8h.6 85.3 8h.5 BrQMB 80.7 7805 81.2 77.6 8003 7807 8102 8106 80.8 7901 Single Legumes Ladino 89.1 90.5 89.8 89.6 90.5 89.6 91.2 90.6 90.2 90.1 Alfalfa 81.9 81.5 8h.0 82.6 8h.5 8h.h 82.2 81.5 83.1 82.5 Mixtures Ladino- orchard 87.1 87.h 89.0 89.h 90.8 88.0 91.8 91.7 89.7 89.1 Ladino- brome 82.5 82.5 8h.3 81.5 85.6 83.3 86.7 85.9 8h.8 83.2 Alfalfa- OrChard 8703 8700 8705 8307 88.0 8706 8705 8708 8706 8605 Alfalfa- brome 80.7 80.5 83.0 81.2 81.9 81.6 8b.? 80.7 82.6 81.0 Average 8h.1 8h.0 85.h 83.h 85.9 8h.8 86.h 85.7 85.h 8h.h 12 Table 5 -- Average Yield of Corn in Bushels per Acre Comparing Fertilizer with no Fertilizer on Beets but Regardless of Whether or not Forage was Removed. _r_ Average Yield of Corn in Bushelsgper Acre Forage Species Pounds of 2-lh-8 Fertilizer Applied per Acre and Mixtures O hOO 800 1600 Average Fertilizer On Off On Off On Off On Off On Off Check 82.9 8h.9 82.7 8h.2 8h.2 85.0 85.9 86.0 83.9 85.0 Single Grasses Orchard 85.0 8209 8600 81.5 87.2 85.1 8709 8309 8605 8303 Brome 82.3 76.8 80.5 77.6 81.2 77.7 82.5 80.3 81.6 78.1 Single Legumes Ladino 89.2 90.3 88.1 91.2 90.9 89.1 89.5 92.3 89.h 90.7 Alfalfa 81.5 81.9 83.8 82.8 82.9 86.0 81.3 82.h 82.h 83.3 Mixtures Ladino- orchard 89.3 85.3 91.9 86.5 91.0 87.7 93.9 89.6 91.5 87.3 Ladino- brome 83.6 81.3 83.6 82.2 8h.5 8h.h 85.h 87.1 8h.3 83.7 Alfalfa- orchard 86.9 87.3 83.7 87.h 86.5 89.0 85.5 89.7 85.6 88.3 Alfalfa- brono 81.6 79.6 82.1 81.9 81.6 81.9 85.1 80.2 82.6 80.9 Average 8’40? 83014 811.07 83.9 8505 8501 86.3 8507 8503 81305 13 The average response to 1600 pounds of 2-lh-8 previously applied, for ladino and mixtures containing ladino was 2.8 bushels per acre in comparison to a 1 bushel increase for alfalfa and mixtures containing alfalfa and a 1.9 bushel average increase for brome and orchard grass alone. The check plot where no forage seedings were made showed an in- crease of 2.1 bushels per acre on those plots receiving 1600 pounds per acre on the original forage seedings over those where no fertilizer was applied. The average corn yields from plots where the forage was left on was higher for every forage species and mixture than yields where the hay was removed (Table h). This difference is highly significant (Table 1) although the difference in actual corn yields were small. The increase in corn yields resulting from applying 800 pounds of 3-9-18 on the beets was highly significant over yields where no ferti- lizer was previously applied on the beets (Table 1) but 20 out of h5 pairs of figures in Table 5 indicate that fertilizer on the beets did not benefit corn yields. The increases ranged from .6 to h.2 bushels per acre. A difference of 2.7 bushels in favor of no fertilizer over fertilizer on beets was found following the alfalfa-orchard grass mixture. The smallest difference favoring no fertilizer on beets was .9 bushel after alfalfa alone. Additional fertilizer on sugar beets resulted in increased average corn yields on all of the original fertilizer plots (Table 5). The largest difference between fertilizer and no fertilizer 6n beets (1.3 bushel) was noted on the check plots and the smallest difference (.h bushel) was found on those plots which received 800 pounds of 2-1h-8. It will be noted from Table 6 that fertilizer on the beets re- sulted in significantly higher corn yields on those plots following forages when compared to the check plots where no forage seeding was made. The use of fertilizer on the beets produced significantly better corn yields following ladino and alfalfa alone than it did after or- chard and brome grass alone. There was a significant difference in yield following mixtures containing ladino over those containing al- falfa as a result of fertilizer on the beets. When all of the forage combinations (Table 6) were compared with each other, a highly signi- ficant difference existed in the way in which they responded in corn yields to fertilizer on the beets. The average oat yields from.plots where the hay had previously been left on were higher than where the hay was removed except on those plots where 1600 pounds of 2-1h-8 was applied in the original applicap tion (Table 7). The largest average oat yield was on plots which pre- viously had received 800 pounds of 2-1h-8 and had the hay left on. The smallest oat yield was obtained where hOO pounds of fertilizer was ap- plied originally and the hay was removed. The yields from the check plots were exceeded only by those where 800 pounds were applied and the hay was left on. 15 Table 6 - The Division of the Interaction of Forage Species and Mixtures, and Fertilizer 0n Single Degrees of Freedom. Beets (m x a) into Source of Variation DF SS MS F Check: Mixtures 1 h9.32 h9.32 5.37* Singles: Combinations 1 1.08 1.08 Grass: Legumes 1 238.52 23h.52 25.50** Within Grasses l .88 .88 'Within Legumes 1 1.36 1.36 Within Combinations g x a 1 .98 .98 l x a 1 99.62 99.62 10.80** g x l x a 1 199.06 199.06 31.70** 'Error A from Table l lhh 1323.75 9.19 * Significant at 5% Level ** Significant at 1% Level 16 Table 7 -— The Average Yield of Oats in Bushels per Acre Regardless of Forage Species and Mixtures and Whether or not the Beets were Fertilized. Pbunds of Average Yield of Oats in Bushels per Acre 2-18-8 Hay 011 Ray Off 0 115.2 Nil-9 3400 MM; 112.1; 800 116.7 1114.1. 1600 1.3.1 1124.3 Average hh.9 hh.0 17 DISCUSSION The yield averages of the corn did not follow the yield pattern of the sugar beets preceding the corn reported by Erdmann (2). The largest yield of corn followed ladino clover; however, the previous beet yield following the original ladino plots was exceeded by yields from ladino-orchard, alfalfa, and orchard grass. The greatest yield of beets was obtained from the ladino-orchard grass plots and were exceeded in corn yield only by plots previously in ladino. The lowest yields of both corn and beets were obtained following brome grass. The fertilizers applied to both the forages and the beets were low in nitrogen. Harrison and Rather (17), found brome grass very responsive to nitrogen; consequently, the low corn yield on the brome grass plots might be a reflection of the lack of necessary nitrogen for adequate growth. The difference in average bushels produced between the highest and lowest yielding plots (those following ladino alone and brome grass alone) was greater than the difference between average yields after no fertilizer on the orginal forages and a 1600 pound application of 2-lh-8. This indicates that forage species and mixtures were comparatively more effective on corn yields than was the fertilizer applied on the forages. 'Work done by Harrison EE.§E' (6), Nielson.gt El. (5), and Andharia 23 51. (1h), showed alfalfa in a rotation resulted in increased avail- ability of residual phosphorous, higher amounts of organic matter and nitr0gen, as well as increased yields. The corn yields following beets after alfalfa in this experiment did not bear out these results. The data indicates that the large yields of forage and beets following 18 alfalfa might have depleted the nutrients causing lower corn yields. The data, however, do not support this theory because even though the corn yield where alfalfa was left on is greater than where it was re- moved, the average corn yield following alfalfa is exceeded by all for- ages except brome and alfalfarbrome. Pieters (9) stated, "It has long been known that crops differ in their effect on succeeding crops, but practically nothing is known as to the cause of the phenomenon". Per- haps the best explanation of why corn yields following alfalfa were low is given by Pieters (9). He says, "The failure of a green-manure crop to increase yields is not uncommon, but such bad results are be- lieved to be due to special conditions, many of which may be corrected with increasing knowledge." Erdmann (2) reported that a limited amount of forage was produced by volunteer alsike clover and weeds on the check plot. Under the con- ditions of this experiment the corn yield on the check plot was higher than corn yields following alfalfa, alfalfa-brome, brome, and ladino- brome. These results indicate that perhaps it would be more advanta- geous to plow down weeds and volunteer vegetation rather than a seeded forage but the economic value of the forage for livestock roughage must be considered in comparing the value of the two practices. The difference (h.1 bushels) between average corn yields following legumes alone and grasses alone is highly significant in favor of the legumes. This is in accordance with the results reported by Harrison 33 El. (6), stating that mixtures containing alfalfa produced signifi- cant increases in corn yields over mixtures which did not contain a1- falfa. 19 The average corn yield following orchard grass was 5 bushels greater than the yield after brome grass alone. This difference is highly significant. The superiority of orchard grass to brome grass in affecting corn yields is reflected in a comparison of mixtures containing orchard grass and mixtures containing brome grass. This comparison shows a difference of 5.3 bushels in favor of orchard grass. A highly significant difference (7.3 bushels) favoring ladino is noted when corn yields following ladino and alfalfa alone are come pared. Likewise yields were better following mixtures containing ladino by 2.3 bushels than yields after mixtures containing alfalfa. The practice of plowing down all of the forage resulted in sig- nificantly better average corn yields than removing the forage. This relationship was true following all forages and after all of the original applications of 2-lh-8. This substantiates the widely ac- cepted fact that the value of forages in a rotation is reduced if the t0p growth is removed from the land and no livestock manure is returned. Harrison gt El. (6) reported continuous pasturing and subsequent return of manure produced significantly higher corn yields than the practice of cutting hay from the first crop and second crop pasture or hay alone. Even though 800 pounds of 3-9-18 on beets produced a significant carry-over increase in average yields of corn, there were many plots on which the higher yields were obtained following no fertilizer. .Average yields after alfalfa-orchard and on the check plots were higher in every case where no fertilizer was applied on the beets. The corn yields following single grass species were consistently higher where fertilizer was applied on the beets than where it was not. The average c0rn.yie1ds following single legumes were higher where beets were not fertilized than 20 where they were fertilized in every case except two. This contrast in response seems to indicate that nitrogen was the limiting factor. Even though the fertilizer was low in nitrogen, it produced a response following grasses but evidently nitrogen was not limiting following legumes as corn yields on these plots showed no response to fertilizer. It is difficult to explain why corn yields following both mix- tures containing ladino responded to fertilizer on beets whereas corn yields from only one of the mixtures containing alfalfa (alfalfa-brome) benefited from such a practice. If it is assumed that the difference was because the orchard grass did not use as much of the nitrogen fixed by the alfalfa as did the brome grass, then why wasn't the same relationship evident in the case of ladino clover inasmuch as the data indicates ladino was generally more beneficial to the corn yields than was alfalfa. The cat yields follow no definite pattern but show that even though forages were beneficial in a rotation, they were no substitute for re- gular applications of commercial fertilizer. This observation is also reported by Gardner and Robertson (8). The fertilizer applied in 1950 was beneficial to yields of forage, beets, and corn but this effect was no longer evident in oat yields in l95h. This experiment was conducted on land which had not grown a sod crop over 20 years prior to 1950. The soil is quite heavy and.even though it was tiled in 1950 at h rod intervals, it is impossible to work it very early in the spring. The past cropping methods have evidently resulted in poor soil structure and consequent improper drainage. During a period of heavy rainfall in 1952, water was standing in several places on the experimental area. While the surface Soil appears to have 21 a fairly good structure, the soil below the plow layer is apparently too tight to allow proper drainage and aeration. It is very possible the effect of the forage species and mixtures used in this experiment would be easier to understand if after the land was deep tilled and a balanced rotation followed for several years, this experiment was repeated. 22 l. 2. 3. h. S. 6. SUMMARY A field seeded to various forage crops in 1950 and managed in different ways in 1951, was plowed and sown to beets in 1952, was planted to corn in 1953, and sown to oats in l95h to measure any carry-over of the previous forage crops. Under the conditions of this experiment, there was a marked difference in the way forages affected subsequent corn yields. Ladino clover and mixtures containing ladino resulted in higher subsequent corn yields than did alfalfa and mixtures contain- .ing alfalfa. Corn yields following the two mixtures containing orchard grass were higher than those after the two mixtures contain- ing brome grass. The response of corn to the original fertilizer application on the forages was not significant. The corn yields from plots where the forage had been previously left on were higher for every forage species and mixture than yields where the hay was removed. 23 7. 8. 9. 10. The increase in corn yields resulting from the application of 800 pounds of 3-9-18 on the beets preceding corn was high- ly significant over yields where no fertilizer was applied. The fertilizer applied in 1950 while beneficial to yields of forage in 1951 and beets in 1952, did not benefit corn in 1953 and oats in l95h. Oat yields in l95h were generally higher on plots where the hay had been previously left on in 1951. The results of this experiment indicate that even though forages are beneficial in a rotation, they are not a sub- stitute for periodic, liberal applications of commercial fertilizer. 2h l. 2. 3. h. 5. 6. LITERATURE CITED Soils and Men, Yearbook of Agriculture, 1938. Erdmann, M. H., The effect of forage management on a subse- quent sugar beet crop, Ph.D. Thesis, 1953, Mich. State College. Purvis, E. R. and Blume, J. M., The role of green manures in potato production. American Potato Journal, Vol. 16, 1939, pp. 32-360 Hester, Jackson B., The value of cover crops in potato pro- duction in Eastern Virginia. American.Potato Journal, Vol. It, 1937. pp. 9-18. Nielsen, K. Fe, Pratt, P. Fe, and. Martin, We Po, Influence Of alfalfa green manure on the availability of phosphorous to corn. Proceedings of Soil Science Society of America, January, 1953, P0 ’46. Harrison, 0. H., Brown, H. M., and Rather, H. 0., The production of forage crop mixtures under different systems of management and consequent effect on corn yields, and the re-establishment of alfalfa. Journal of The American Society of Agronomy, Vol. 39, 19h7: PP. 21h-223. 25 7. 8. 9. 10. 12. MCKraig, Nelson, Jr., Carns, W. A., and Bowen, A. B., Soil organic matter and nitrogen as influenced by green manure crop management on Norfolk coarse sand. Journal of American Society of Agron., Vol. 32, 19h0, pp. 8&2-852. Gardner, Robert, and.R0bertson, D. W., The effect of alfalfa on the yields of non-leguminous crops in a rotation. Proc. of American Soc. of Sugar Beet Tech., 1952, pp. 22h-228. Pieters, Adrian J., Green.Manuring Principles and Practice, John Wiley and Sons, New York, 1927. Nelson, Martin, Effect of the use of winter legumes on.yields of cotton, corn and rice. Arkansas Agr. Exp. Station, Bul. h51, l9hh. Tidmore, J. W., and Volk, N. J., The effect of plowing under and the time of plowing under legumes on the conservation of nitrogen. Journal of the Amer. Soc. of Agron., Vol. 37, l9h5, pp. 1005-1010. Moser, Frank, Influence of leguminous plant additions on the organic matter content and available nutrient supply of southern soils. Journal of the Amer. Soc. of Agron., V01. 3h, 19h2, PP. 711’7190 26 13. 1h. 15. 16. 17. Robertson, L. S., A study of the effects of seven.systems of cropping upon yields and soil structure. Proc. of the Amer. Soc. of Sugar Beet Tech., 1952, pp. 255-26h. Andharia, R. M., Stanford, G., and Schaller, F. W., Nitrogen status of Marshall silt loam as influenced by various crop ro- tations. Proc. Soil Science Soc. of America, July, 1953, p. 2h7. Crowther, E. M. and Mirchandani, T. J., Winter leaching and the manurial value of green manures and crop residues for winter wheat. Journal of Agr. Science, Vol. 21, 1931, pp. h93-525. Bushnell, John, Non-legumes as green manures for potatoes. Proc. of the Amer. Soc. of Hort. Science, V01. 33, 1935, pp. 566-568. Rather, H. C. and Harrison, 0. M3, Alfalfa and smooth brome grass for pasture and hay. ZMich. Agr. Exp. Station Circular Bulletin 189, 1911;. 27 ROOM USE ONLY “1111111111111“